1. Field of the Invention
The present invention relates to a robot system having an image processing function of detecting three-dimensional position and posture (orientation) of an object, and in particular to a robot system having an image processing function suitable for a bin-picking operation of taking out a workpiece one by one from a randomly arranged stack of workpieces.
2. Description of Related Art
An operation of taking out an individual workpiece form a randomly arranged stack of workpieces or an aggregation of workpieces contained in a container of a predetermined size, which have identical shapes and different three-dimensional positions/postures, have been performed manually. In storing workpieces in a pallet or placing workpieces at a predetermined position in a machine or a device using a (dedicated) robot, since it has been impossible to directly take out an individual workpiece one by one from the randomly arranged stack of workpieces by the dedicated robot, it has been necessary to rearrange the workpieces in advance so as to be picked out by the robot. In this rearrangement operation, it has been necessary to take out an individual workpiece from the stack manually.
The reason why individual workpieces having identical shapes and different three-dimensional positions/postures can not be picked out by a robot from a randomly arranged stack of workpieces or an aggregation of workpieces contained in a container is that the position/posture of individual workpieces in the stack or the aggregation can not be recognized, so that a robot hand can not be placed to a suitable position/posture at which the robot hand can hold the individual workpiece.